Semiotic codes vary in their complexity of structure or 'articulation'. The term articulation, as used by semioticians with reference to 'code structure', was derived from André Martinet's structural linguistics. The term can be misleading, since everyday usage might lead one to assume that it relates to how 'articulate' individuals are. Presumably because of this potential confusion, theoretical linguists have largely abandoned the use of the term articulation in the structural sense, preferring to refer to 'duality of patterning', but semioticians continue to use the term. Its semiotic usage is rather more closely related to the sense in which lorries (trucks) can be 'articulated' - that is, having separable sections which are linked together. Pierre Guiraud comments on semiotic articulation:
Following the model of verbal language, an articulated code has a 'vocabulary' of basic units together with syntactical rules which can be used to generate larger meaningful combinations (Innis 1986, 88-9, 99-102). A semiotic code which has 'double articulation' (as in the case of verbal language) can be analysed into two abstract structural levels: a higher level called 'the level of first articulation' and a lower level - 'the level of second articulation' (Nöth 1990; Eco 1976, 231ff). The traffic sign lacks double articulation, but rather than having no articulation, it would more commonly be referred to as having first articulation only.
At the level of first articulation the system consists of the smallest meaningful units available (e.g. morphemes or words in a language). In language this level of articulation is called the grammatical level. The meaningful units at this level are complete signs, each consisting of a signifier and a signified. Where codes have recurrent meaningful units (such as the Olympic sports pictograms and textile care symbols), they have first articulation. In systems with double articulation, these signs are made up of elements from the lower (second) level of articulation.
At the level of second articulation, a semiotic code is divisible into minimal functional units which lack meaning in themselves (e.g. phonemes in speech or graphemes in writing). These purely differential structural units (called figurae by Hjelmslev) are recurrent features in the code. They are not signs in themselves (the code must have a first level of articulation for these lower units to be combined into meaningful signs). These lower units are nonsignifying sign elements. In a code with both levels (a 'double articulated' system) the function of these lower units is purely to differentiate the minimal meaningful units. In language, the phonemes /b/, /p/ and /t/ are elements of second articulation, the function of which is to distinguish between words, such as /pin/, /bin/ and /tin/, which are elements of the first articulation of language. In language, the level of second articulation is thus a phonological level.
Semiotic codes have either single articulation, double articulation or no articulation. Double articulation enables a semiotic code to form an infinite number of meaningful combinations using a small number of low-level units (offering economy and power). The infinite use of finite elements is a feature which in relation to media in general has been referred to as 'semiotic economy'. Traditional definitions ascribe double articulation only to human language, for which this is regarded as a key 'design feature' (Hockett 1958; Hockett 1960; Hockett 1965). Louis Hjelmslev regarded it as an essential and defining feature of language (Hjelmslev 1961). Double articulation is seen as being largely responsible for the creative economy of language. Language is a semiotic system which is highly economical - employing only a small number of signs. Amongst other advantages, linguistic economy facilitates learning and recall. As for creativity, language is infinitely productive. The English language, for instance, has only about 40 or 50 elements of second articulation (phonemes) but these can generate hundreds of thousands of words. Similarly, from a limited vocabulary we can generate an infinite number of sentences (subject to the constraint of syntax which governs structurally valid combinations). Consequently, as Noam Chomsky has noted, the creative economy of language gives us the power to endlessly generate sentences which we have never encountered before. It is by combining words in multiple ways that we can seek to render the particularity of experience. If we had individual words to represent every particularity we would have to have an infinite number of them, which would exceed our capability of learning, recalling and manipulating them. John Lyons comments that 'duality, as it operates in language, is also bound up with arbitrariness. If each phonological element in a given form had to bear an identifiable iconic relationship, whether conventional or natural, to some aspect of its meaning, it is obvious that there would be severe constraints upon the possibility of combining phonological elements with one another' (Lyons 1977, 74). Roman Jakobson observed that
As Jakobson notes, even beyond the level of the sentence, the ways in which we use words are subject to linguistic conventions which limit the possibilities open to us. If we depart too far from the norms, we may fail to communicate.
Double articulation does not seem to occur in the natural communication systems of animals other than humans. As to other human semiotic systems with double articulation, Nöth notes that these include systematic codes used in library or warehouse catalogues, and 'many codes of data-processing'. He adds that 'there has been much discussion about the structure of codes such as architecture, photography, film, sign language and narratives, but no convincing conclusion has been reached concerning the articulation of these codes' (e-mail 12/8/97). Susanne Langer claims that whilst visual media such as photography, painting and drawing have lines, colours, shadings, shapes, proportions and so on which are 'abstractable and combinatory', and which 'are just as capable of articulation, i.e. of complex combination, as words', they have no vocabulary of units with independent meanings (Langer 1951, 86-7).
Rather than dismissing 'non-discursive' media for their limitations, however, Langer argues that they are more complex and subtle than verbal language and are 'peculiarly well-suited to the expression of ideas that defy linguistic "projection"'. She argues that we should not seek to impose linguistic models upon other media since the laws that govern their articulation 'are altogether different from the laws of syntax that govern language'. Treating them in linguistic terms leads us to 'misconceive' them: they resist 'translation' (ibid., 86-9).
Some codes have first articulation only. These semiotic systems consist of signs - meaningful elements which are systematically related to each other - but there is no second articulation to structure these signs into minimal, non-meaningful elements. Where the smallest recurrent structural unit in a code is meaningful, the code has first articulation only. Many semioticians argue that nonverbal communication and the various systems of animal communication have only first articulation. Nöth notes that although bird calls make use of basic units, each of these is a complete message, so bird calls have first articulation only (Nöth 1990, 151). Other examples include hotel and office room numbers where the first digit indicates the floor and the second indicates the serial number of the room on that floor. The system of related traffic signs (with red borders, triangular or circular shapes, and standardized, stylised images) is a code with first articulation only (Eco 1976, 232). Some semioticians (such as Christian Metz) argue that codes based on motivated signs - such as film and television - lack second articulation. Metz declared that in film, 'it is impossible to break up the signifier without getting isomorphic segments of the signified' (cited in Nöth 1990, 469).
Other semiotic codes lacking double articulation have second articulation only. These consist of signs which have specific meanings which are not derived from their elements. They are divisible only into figurae (minimal functional units). Nöth suggests that 'the most powerful code with second articulation only is the binary code of information theory' (e-mail, 12/8/97): this has only 2 minimal functional units, 0 and 1, but these units can be combined to generate numbers, letters and other signs. A rather less powerful system with second articulation only is that of accession codes for books, which are simply serial numbers.
Codes without articulation consist of a series of
signs bearing no direct relation to each other. These signs are not
divisible into recurrent compositional elements. The folkloristic 'language of
flowers' is a code without articulation, since each type of flower is an
independent sign which bears no relation to the other signs in the code.
Unarticulated codes, which have no recurrent features, are 'uneconomical'.
Some commentators have proposed more than two levels of articulation in verbal language, but Guiraud argues that:
Umberto Eco argued that cinema has a triple articulation: iconic figures; semes (combinations of iconic figures); and kinemorphs (combinations of semes) (Stam 2000, 114).
The notion of articulation is, in short, a way of dividing a semiotic system into basic levels: in the case of verbal language the levels can be termed those of sound and meaning. This clearly relates to the Saussurean analytical division of the sign into a 'sound-image' (signifier) and a concept (signified). In a semiotic system with double articulation the levels of the signifier and of the signified are relatively autonomous.
Denotation, connotation and myth are also described semiotically in terms of levels (the 'orders of signification' of Hjelmslev and Barthes). More generally, Saussure noted that signs can themselves contain signs, as in the case of a 'complex sign' such as the word 'twenty-nine' which contains the 'simple signs' twenty and nine (Saussure 1983, 130; Saussure 1974, 131). On a larger scale, an entire text is a sign which may be composed of any number of other signs (Saussure 1983, 127; Saussure 1974, 128).
Related to the idea of levels of articulation in a semiotic system is the notion of modelling systems, since 'secondary modelling systems' are described as superstructures built upon 'primary modelling systems'. Some theorists, following Yuri Lotman, refer to language in these terms. Within this framework, writing is a secondary modelling system and written texts are built upon a primary modelling system which consists of spoken language. Secondary modelling systems are thus presented as if they constitute signs of signs or representations of representations (Culler 1985, 122). Saussure adopted this position, noting that 'a language and its written form constitute two separate systems of signs. The sole reason for the latter is to represent the former' (Saussure 1983, 24; Saussure 1974, 23). Since this stance grants primacy to the spoken form, it has been criticized (notably by Jacques Derrida) as phonocentric (Derrida 1976). If we grant that even perception involves encoding, then speech is as 'secondary' as any other sign-system. Despite his own phonocentrism, Marshall McLuhan emphasized the power of the written word, alluding to its basis in arbitrariness on both structural levels: 'By the meaningless sign [written letters] linked to the meaningless sound we have built the shape and meaning of Western man' (McLuhan 1962, 50). Other theorists have extended the notion of modelling systems to 'texts' in other media, seeing them as secondary modelling systems built out of a primary 'language'. Literary texts have been seen as a second order modelling system built upon the primary linguistic system or upon the modelling system of the written word (Silverman 1983, 27; Sturrock 1986, 103). Cinematic texts have sometimes been seen as built upon a primary modelling system of 'graphic language' (Altman 1999, 175). However, whether a graphical 'language' has basic building blocks and what these might be has been hotly disputed.